Signalling in coordinated multi-point transmission and reception (CoMP)

Abstract

In a wireless communications system including a first base station and a second base station, a wireless communications method implemented in the first base station supporting coordinated multi-point transmission and reception (CoMP) is disclosed. The wireless communications method comprises receiving from the second base station an information element (IE) indicating multiple relative narrowband Tx (transmit) power (RNTP) thresholds, and performing interference aware scheduling. Other methods, systems, and apparatuses also are disclosed.

What is claimed is: 
     
       1. A wireless communication method for a first base station supporting coordinated multi-point transmission and reception (CoMP) in a wireless communication system including the first base station and a second base station, the wireless communications method comprising:
 receiving, from the second base station, an information element (IE) indicating enhanced Relative Narrowband Tx (transmit) Power (eRNTP) and multiple eRNTP thresholds, the eRNTP being represented by a bitmap for each physical resource block (PRB) in the second base station; and 
 performing interference aware scheduling based on the eRNTP, 
 wherein:
 the bitmap is represented by any of {00, 01, 10, 11}, and 
 each of the thresholds is represented by any of {−∞, −11, −10, −9, −8, −7, −6, −5, −4, −3, −2, −1, 0, 1, 2, 3}, 
 
 wherein the IE further includes:
 number of cell-specific antenna ports; 
 physical downlink control channel (PDCCH) interference impact; 
 starting system frame number (SFN); and 
 starting subframe index, and 
 
 wherein:
 a “00” value of the bitmap indicates not exceeding a first RNTP threshold, 
 a “01” value of the bitmap indicates not exceeding a second RNTP threshold higher than the first RNTP threshold, and 
 a “11” value of the bitmap indicates no promise on the Tx power is given. 
 
 
     
     
       2. A wireless communication method for a second base station supporting coordinated multi-point transmission and reception (CoMP) in a wireless communication system including a first base station and the second base station, the wireless communications method comprising:
 transmitting, to the first base station, an information element (IE) indicating enhanced Relative Narrowband Tx (transmit) Power (eRNTP) and multiple eRNTP thresholds, the eRNTP being represented by a bitmap for each physical resource block (PRB) in the second base station, 
 wherein the first base station performs interference aware scheduling based on the eRNTP, 
 wherein:
 the bitmap is represented by any of {00, 01, 10, 11}, and 
 each of the thresholds is represented by any of {−∞, 11, −10, −9, 8, −7, −6, −5, −4, −3, −2, −1, 0, 1, 2, 3}, 
 
 wherein the IE further includes:
 number of cell-specific antenna ports; 
 physical downlink control channel (PDCCH) interference impact; 
 starting system frame number (SFN); and 
 starting subframe index, and 
 
 wherein:
 a “00” value of the bitmap indicates not exceeding a first RNTP threshold, 
 a “01” value of the bitmap indicates not exceeding a second RNTP threshold higher than the first RNTP threshold, and 
 a “11” value of the bitmap indicates no promise on the Tx power is given. 
 
 
     
     
       3. The wireless communication method of  claim 2 , further comprising:
 deciding the multiple RNTP thresholds. 
 
     
     
       4. A first base station supporting coordinated multi-point transmission and reception (CoMP) in a wireless communication system including the first base station and a second base station, the first base station comprising:
 a receiver to receive, from the second base station, an information element (IE) indicating enhanced Relative Narrowband Tx (transmit) Power (eRNTP) and multiple eRNTP thresholds, the eRNTP being represented by a bitmap for each physical resource block (PRB) in the second base station; and 
 a controller to perform interference aware scheduling based on the eRNTP, 
 wherein:
 the bitmap is represented by any of {00, 01, 10, 11}, and 
 each of the thresholds is represented by any of {−∞, −11, −10, −9, −8, −7, −6, −5, −4, −3, −2, −1, 0, 1, 2, 3}, 
 
 wherein the IE further includes:
 number of cell-specific antenna ports; 
 physical downlink control channel (PDCCH) interference impact; 
 starting system frame number (SFN); and 
 starting subframe index, and 
 
 wherein:
 a “00” value of the bitmap indicates not exceeding a first RNTP threshold, 
 a “01” value of the bitmap indicates not exceeding a second RNTP threshold higher than the first RNTP threshold, and 
 a “11” value of the bitmap indicates no promise on the Tx power is given. 
 
 
     
     
       5. A second base station supporting coordinated multi-point transmission and reception (CoMP) in a wireless communication system including a first base station and the second base station, the second base station comprising:
 a controller to decide enhanced Relative Narrowband Tx (transmit) Power (eRNTP) and multiple eRNTP thresholds, the eRNTP being represented by a bitmap for each physical resource block (PRB) in the second base station; and 
 a transmitter to transmit, to the first base station, an information element (IE) indicating the eRNTP and the multiple eRNTP thresholds, 
 wherein the first base station performs interference aware scheduling based on the eRNTP, 
 wherein:
 the bitmap is represented by any of {00, 01, 10, 11}, and 
 each of the thresholds is represented by any of {−∞, −11, −10, −9, 8, −7, −6, −5, −4, −3, −2, −1, 0, 1, 2, 3}, 
 
 wherein the IE further includes a single bitmap in which each position:
 number of cell-specific antenna ports; 
 physical downlink control channel (PDCCH) interference impact; 
 starting system frame number (SFN); and 
 starting subframe index, and 
 
 wherein
 a “00” value of the bitmap indicates not exceeding a first RNTP threshold, 
 a “01” value of the bitmap indicates not exceeding a second RNTP threshold higher than the first RNTP threshold, and 
 a “11” value of the bitmap indicates no promise on the Tx power is given. 
 
 
     
     
       6. A wireless communication method for a wireless communication system supporting coordinated multi-point transmission and reception (CoMP) and including a first base station and a second base station, the wireless communication method comprising:
 transmitting, from the second base station to the first base station, an information element (IE) indicating enhanced Relative Narrowband Tx (transmit) Power eRNTP and eRNTP thresholds, the eRNTP being represented by a bitmap for each physical resource block (PRB) in the second base station; and 
 performing, at the first base station, interference aware scheduling based on the eRNTP, 
 wherein:
 the bitmap is represented by any of {00, 01, 10, 11}, and 
 each of the thresholds is represented by any of {−∞, −11, −10, −9, −8, −7, −6, −5, −4, −3, −2, −1, 0, 1, 2, 3}, 
 
 wherein the IE further includes:
 number of cell-specific antenna ports; 
 physical downlink control channel (PDCCH) interference impact; 
 starting system frame number (SFN); and 
 starting subframe index, and 
 
 wherein:
 a “00” value of the bitmap indicates not exceeding a first RNTP threshold, 
 a “01” value of the bitmap indicates not exceeding a second RNTP threshold higher than the first RNTP threshold, and 
 a “11” value of the bitmap indicates no promise on the Tx power is given. 
 
 
     
     
       7. A wireless communication system supporting coordinated multi-point transmission and reception (CoMP), the wireless communication system comprising:
 a first base station; and 
 a second base station transmitting, to the first base station, an information element (IE) indicating enhanced Relative Narrowband Tx (transmit) Power eRNTP and multiple eRNTP thresholds, the eRNTP being represented by a bitmap for each physical resource block (PRB) in the second base station, 
 wherein the first base station performs interference aware scheduling based on the eRNTP, 
 wherein:
 the bitmap is represented by any of {00, 01, 10, 11}, and 
 each of the thresholds is represented by any of {−∞, −11, −10, −9, −8, −7, −6, −5, −4, −3, −2, −1, 0, 1, 2, 3}, 
 
 wherein the IE further includes:
 number of cell-specific antenna ports; 
 physical downlink control channel (PDCCH) interference impact; 
 starting system frame number (SFN); and 
 starting subframe index, and 
 
 wherein:
 a “00” value of the bitmap indicates not exceeding a first RNTP threshold, 
 a “01” value of the bitmap indicates not exceeding a second RNTP threshold higher than the first RNTP threshold, and 
 a “11” value of the bitmap indicates no promise on the Tx power is given. 
 
 
     
     
       8. A user equipment (UE) used in a wireless communication system including a first base station and a second base station, the UE comprising:
 a receiver configured to receive, from the first base station, a reference signal; and 
 a transmitter configured to transmit, to the first base station, information of received power, 
 wherein the receiver further configured to receive, from the first base station, a downlink signal in each physical resource block (PRB) with a transmission power determined by the first base station based on the information, 
 wherein the determined transmission power is reported, to the second base station, as an information element (IE) for interference scheduling, the IE indicating enhanced Relative Narrowband Tx (transmit) Power (eRNTP) and multiple eRNTP thresholds, 
 wherein the eRNTP is represented by a bitmap for each PRB in the first base station, 
 wherein the bitmap is represented by any of {00, 01, 10, 11}, a “00” value of the bitmap indicating not exceeding a first RNTP threshold, a “01” value of the bitmap indicating not exceeding a second RNTP threshold higher than the first RNTP threshold, and a “11” value of the bitmap indicates no promise on the Tx power is given, 
 wherein each of the thresholds being represented by any of {−∞, −11, −10, 9, −8, −7, −6, −5, −4, −3, −2, −1, 0, 1, 2, 3}, and 
 wherein the IE further includes number of cell-specific antenna ports, physical downlink control channel (PDCCH) interference impact, starting system frame number (SFN), and starting subframe index. 
 
     
     
       9. A communication method implemented in a user equipment (UE) used in a wireless communication system including a first base station and a second base station, the communication method comprising:
 receiving, from the first base station, a reference signal; 
 transmitting, to the first base station, information of received power; and 
 receiving, from the first base station, a downlink signal in each physical resource block (PRB) with a transmission power determined by the first base station based on the information, 
 wherein the determined transmission power is reported, to the second base station, as an information element (IE) for interference scheduling, the IE indicating enhanced Relative Narrowband Tx (transmit) Power (eRNTP) and multiple eRNTP thresholds, 
 wherein the eRNTP is represented by a bitmap for each physical resource block (PRB) in the first base station, 
 wherein the bitmap is represented by any of {00, 01, 10, 11}, a “00” value of the bitmap indicating not exceeding a first RNTP threshold, a “01” value of the bitmap indicating not exceeding a second RNTP threshold higher than the first RNTP threshold, and a “11” value of the bitmap indicates no promise on the Tx power is given, 
 wherein each of the thresholds being represented by any of {−∞, −11, −10, 9, −8, −7, −6, −5, −4, −3, −2, −1, 0, 1, 2, 3}, and 
 wherein the IE further includes number of cell-specific antenna ports, physical downlink control channel (PDCCH) interference impact, starting system frame number (SFN), and starting subframe index.